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Cod sursa(job #371015)
#include <fstream>
#include <list>
#include <vector>
#define MAX 220
#define inf 2000000000
using namespace std;
ifstream fi("cc.in");
ofstream fo("cc.out");
int N,DHeap,Dist[MAX],heap[MAX],T[MAX],C[MAX][MAX],F[MAX][MAX],poz[MAX];
vector<pair<int,int> > G[MAX],Gi[MAX];
list<int> L;
int BellmanFord(int S,int D){
for (int i=1;i<=N;++i){ Dist[i]=inf;T[i]=-1; }
Dist[S]=0;
L.push_back(S);
while (!L.empty()){
list<int>::iterator it=L.begin();
for (unsigned int i=0;i<G[*it].size();++i)
if (C[*it][G[*it][i].first]-F[*it][G[*it][i].first]>0)
if (Dist[G[*it][i].first]>(Dist[*it]+G[*it][i].second)){
T[G[*it][i].first]=*it;
Dist[G[*it][i].first]=Dist[*it]+G[*it][i].second;
L.push_back(G[*it][i].first);
}
L.pop_front();
}
if (Dist[D]<inf) return 1; else return 0;
}
void swap(int i,int j){
int aux=heap[i];heap[i]=heap[j];heap[j]=aux;
poz[heap[i]]=i;poz[heap[j]]=j;
}
void heap_up(int nod){
int dad=(nod/2);
if (dad && Dist[heap[dad]]>Dist[heap[nod]]){
swap(nod,dad);
heap_up(dad);
}
}
void heap_dw(int nod){
int l=nod*2,r=l+1,minim=nod;
if (l<=DHeap && Dist[heap[l]]<Dist[heap[minim]]) minim=l;
if (r<=DHeap && Dist[heap[r]]<Dist[heap[minim]]) minim=r;
if (minim!=nod){
swap(nod,minim);
heap_dw(minim);
}
}
int Dijkstra(int S,int D){
for (int i=1;i<=N;++i)
for (unsigned int j=0;j<G[i].size();++j)
if (Dist[i]!=inf && Dist[G[i][j].first]!=inf) G[i][j].second+=(Dist[i]-Dist[G[i][j].first]);
DHeap=N;
for (int i=1;i<=N;++i){
Dist[i]=inf;
T[i]=-1;
heap[i]=i;
poz[i]=i;
}
Dist[S]=0;
heap_up(poz[S]);
while (DHeap && Dist[heap[1]]!=inf){
int nod=heap[1];
for (unsigned int i=0;i<G[nod].size();++i)
if (C[nod][G[nod][i].first]-F[nod][G[nod][i].first]>0)
if (Dist[G[nod][i].first]>(Dist[nod]+G[nod][i].second)){
Dist[G[nod][i].first]=Dist[nod]+G[nod][i].second;
T[G[nod][i].first]=nod;
heap_up(poz[G[nod][i].first]);
}
swap(1,DHeap);
--DHeap;
heap_dw(1);
}
if (Dist[D]<inf) return 1; else return 0;
}
int cost(int sursa,int dest){
if (!BellmanFord(sursa,dest)) return 0;
int rez=0;
while (Dijkstra(sursa,dest)){
int maxflow=inf;
for (int nod=dest;nod!=sursa;nod=T[nod]) maxflow=min(maxflow,C[T[nod]][nod]-F[T[nod]][nod]);
if (maxflow>0)
for (int nod=dest;nod!=sursa;nod=T[nod]) { F[T[nod]][nod]+=maxflow; F[nod][T[nod]]-=maxflow; }
}
for (int i=1;i<=(N-2)/2;++i)
for (unsigned int j=0;j<Gi[i].size();++j)
rez+=F[i][Gi[i][j].first]*Gi[i][j].second;
return rez;
}
int main(){
fi>>N;
int x;
for (int i=1;i<=N;++i)
for (int j=1;j<=N;++j){
fi>>x;
G[i].push_back(make_pair(N+j,x));
G[N+j].push_back(make_pair(i,-x));
Gi[i].push_back(make_pair(N+j,x));
C[i][N+j]=1;
}
for (int i=1;i<=N;++i){
C[N*2+1][i]=1;
G[N*2+1].push_back(make_pair(i,0));
G[i].push_back(make_pair(N*2+1,0));
C[N+i][N*2+2]=1;
G[N+i].push_back(make_pair(N*2+2,0));
G[N*2+2].push_back(make_pair(N+i,0));
}
N=N*2+2;
fo<<cost(N-1,N)<<"\n";
fi.close();
fo.close();
return 0;
}